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以天然气为能源，用燃气机代替电动机驱动压缩机并充分利用发动机废热、工业余热以及低品位环境热量的采暖、空调装置——燃气压缩式热泵近年来发展迅速。美国燃气设备的总装机容量已达到1．2GW，日本燃气机热泵占全部燃气制冷设备的29％，总装机容量大约1GW，燃气机热泵在英国、法国、德国、瑞士等都得到了较快的发展与应用。中研究了以天然气为驱动能源的压缩式热泵的特点及能量利用率，分析并测试了该系统的运行特性及交工况特性，进行了各种工况及转速下的实验研究。结果表明，该系统具有较好的部分负荷特性、一次能源利用率及交工况特性，为一种绿色高效的供热空调系统。     

Deactivation of V2O5-WO3-TiO2 SCR catalyst at a biomass-fired combined heat and power plant

The deactivation of a commercial type V₂O₅-WO₃-TiO₂ monolith catalyst under biomass combustion was studied at a full-scale grate-fired power plant burning straw/wood using a slip stream pilot scale reactor. The aerosols in the flue gas consisted of a mixture of potassium chloride and sulphate. Three catalyst elements were exposed at 350 °C, and one element was exposed at 250 °C for comparison. The catalyst activity was measured in the reactor at the exposure temperature by addition of NH₃ and extra NO. The activity, in terms of a first-order rate constant, dropped by 52% after about 1140 h indicating a very fast deactivation compared to coal firing. It was also found that the reactor temperature was not of importance for the deactivation rate. SEM-EDX analysis showed that particle deposition and pore blocking contributed to the deactivation by decreasing the diffusion rate of NO and NH₃ into the catalyst. However, potassium also penetrated into the catalyst wall and the resulting average K/V ratio in the catalyst structure was high enough (about 0.3–0.5) for a significant chemical deactivation. Chemisorption studies carried out in situ showed that the amount of chemisorbed NH₃ on the catalyst decreased as a function of exposure time, which reveals that Brøndsted acid sites had reacted with potassium compounds and thereby rendered inactive. When washed by 0.5 M H₂SO₄ the regenerated catalyst regains a higher activity than that of the fresh catalyst at temperatures higher than 300 °C, but even though reactivation is possible, the deactivation rate appears too high for practical use of the SCR process in straw combustion.     

Effect of oxygen vacancies on transformation of zirconia at low temperatures

The effect of oxygen vacancy on the stability of phase structures and phase transformation of zirconia at low temperatures was studied using an electrochemical technique. It is suggested that the decrease of oxygen vacancies decreases the stability of metastable tetragonal zirconia and promotes its transformation to the monoclinic phase. This revised version was published online in November 2006 with corrections to the Cover Date.     

Mobile robot path planning based on hierarchical hexagonal decomposition and artificial potential fields

In this article, a new algorithm based on an artificial potential field and hierarchical cell decomposition technique is developed to solve the find-path problem for a mobile robot. The complete map of the workspace including obstacle locations is assumed to be known a priori. The basic cell structure used for decomposition is a hexagon. The artificial potential field is based on an attractive force from the goal position and repelling forces from the obstacles. Computer simulations of the algorithm for various obstacle scenarios are also presented. © 1994 John Wiley & Sons, Inc.     

COMMENTS ON THE DETERMINATION OF FRIABILITY AND UNMODIFIED GRAINS

The Analysis Committee of the European Brewery Convention is aware that the Friabilimeter sometimes is used on samples that do not comply with the field of application. The precision of the method is also overlooked by some users. The field of application, precision of the method as well as the need for frequent testing of the instrument is therefore stressed in more detail than in the earlier published method by the EBC Analysis Committee.     

糖厂现用连续离心机的研究及生产实践

在各糖厂现用连续离心机原有生产实践基础上，对其机械吸震、加温、布温、机索结构、物料密封、机座等部件做了进一步改进，并取得可观的实效。     

一种适用于ATM的语音处理方案

以ＡＴＭ实现分组话音通信，需要解决两个基本问题：传输时延和分组丢失。针对这两个基本问题，本文着重讨论了ＡＴＭ分组话音通信中３２ｋｂ／ｓＡＤＰＣＭ话音分组丢失的重建技术－－于模式匹配的波形替代技术和静默重建技术，分别用以补偿由于网络阻塞造成的分组话音信息丢失而产生的失真和改善重建话音的自然性。     

聚苯醚磺酸锂／共聚醚复合物的离子导电性研究

合成了３种不同磺化度的聚苯醚磺酸锂（ＳＰＰＯＬｉ）与Ｐ（ＭＥＯ１６－ＡＭ）／ＳＰＰＯＬｉ复合物。研究了复合物的离子导电性与磺化度，组成比及增塑剂含量的关系。含４０％（ｍａｓｓ）增塑剂的复合物具有单离子导电特征，锂离子迁移数高达０．９７，室温电导率达２×１０－５Ｓ／ｃｍ。     

氧化铝/锌合金复合材料界面的SEM观察

利用挤压铸造制备氧化铝／锌合金复合材料，在扫描电镜（ＳＥＭ）上观察复合材料的界面。结果表明，在复合材料中纤维与基体间存在致密界面层，合金元素通过适当的化学反应可改善纤维与基体间的结合；在凝固过程中，纤维／基体界面上的硅在共晶体的共生生长过程中起了领先相作用，导致复合材料的共晶转变是由铝硅共晶转变和锌铝共晶转变两者组成。     

无线电引信多普勒信号增速器的研究

论述了无线电引信多普勒信号增速器的实现原理及意义，介绍了采用ＴＭＳ３２０Ｃ３０作为ＣＰＵ、多片大容量静态ＲＡＭ芯片构成海量存储体的信号增速器硬件结构和软件设计，并提出了今后的研究方向。